How to Build a Simple Electromagnetic Train

Here is an interesting project for kids that explores both electricity and magnetism – build a simple electromagnetic train!

This intriguing video has been making it’s way around Facebook… it’s a simple electric “train” made out of coiled copper wire and a train car comprised of a battery with magnets on both ends. It was so fascinating that we had to try it!

This project totally works as seen on the video, but there are some things to know first.

Neodymium magnets. Regular magnets are not strong enough. We purchased our neodymium magnets for our magnetic slime project. If you end up ordering some, you should definitely do that project too!

Wire cutters

Safety Note: Neodymium magnets are extremely strong and definitely not for kids who put things in their mouths. In fact, this entire project is not for kids who still put things in their mouths! I store our magnets out of reach of my kids – even the bigger kids. They can be difficult to separate because of their strength and can definitely damage electronic devices. With proper supervision, though, this project is super cool and there is so much to learn! Just be safe.

Step 1: Create your train.

We put 4 magnets on each end of the train. One or two will work fine, but we had plenty so we used four. The original video does not mention this, but the magnets need to be placed on the battery with the poles facing opposite directions. Otherwise, the train will not work. (Just hold the magnets so that they push each other away, then stick the battery in between.)

Step 2: Make your coils.

The coils need to be wrapped pretty closely around the train. I found that wrapping the copper wire around a AA battery made nice even coils that were just the right size for the AAA battery plus the magnets. Once you cut the wire it’s kind of challenging to attach another section, so make a big long train track! I wish I had made ours longer, but I didn’t want to use up the entire 25 foot package if we were doing it wrong, so I cut it off to test it.

Step 3: Run your train!

How the Electro-Magnetic Train Works:

Electricity and magnetism are linked in a way that scientists do not completely understand. Each can create the other. If you wrap a copper wire into coils and run an electrical current through it, you will create a magnetic field. If you rotate a permanent magnet (as opposed to an item that has been magnetized) inside a coil of copper wire, you can create an electrical current.

In this project, the neodymium magnets on the ends of the battery create a bar magnet with a north pole and a south pole. When you put the train inside the coils, it causes an electrical current to flow through the copper wire, which creates a magnetic field in the section of wire coils right around the train car. This magnetic field has its own north and south poles, which push the train along the track. You’ll notice that the train will only run one direction because of it’s magnetic poles. It’s pretty amazing science!

We found that the battery runs down pretty quickly, and I’m not sure why this is. This train works really well for a demonstration, but you’ll probably need a fresh battery each time you get it out.

You can find a much more in-depth explanation of the science behind this project at Skulls in the Stars. He also has some very helpful diagrams in this article. Older students could benefit from drawing their own copy of the diagrams.

Be sure to visit the other posts in the STEAM Power series! So many fun ideas this week.

– Make sure that your wire coils are close to the “train.” In other words, the coils should not be much larger than the train.
– Make sure that the poles of your magnets are facing in opposite directions.
– Try a fresh battery.

Cannot get this to work either. Well, let me clarify. The train moves slightly, but it almost looks slight of hand rather than electromagnetism. I used a 7/16 dowel to coil the copper wire, so it’s close to the battery without being snug at all. I tried 5 neodymium magnets on each end. Some have now broken, so we’re down to 3 on each end. I’ve tried 3 different batteries. The last was purchased from the store 20 minutes ago.

Make sure that the magnets have their poles facing so that north is pointing one direction and south is pointing the other direction. Also, make sure that you use a fresh battery and that the battery is not getting caught on the coils. I hope that helps!

What a super fun idea and project to do with little ones. I love any activity that sparks an interest in electricity. Many don’t think of it as a career option, but introducing your little ones to it early might be a great path for them. Thanks for sharing!

Not working for me either. Coil is bare. Wrapped around AA to ensure proper width. Using 10 total neo magnets, 5 on each side. Magnets push apart, battery in the middle. Nothing happens when placed inside coil.
🙁

I wish I knew what to tell you! The only thing I can think of is to try a fresh battery. This project burns them down pretty quickly. I realize that you haven’t gotten it to work yet, but if it’s short circuiting somewhere it could still run down the battery, maybe?

i just used 20 gauge copper wire coil which is completely bare or coatless and a AA battery and magnets are 12×2 sized neodymium magnet but i found it is not working..and when i kept the battery inside copper loop a sparking noise is generat .but the battery doesn’t move. can you help me out.

I used 18.5 gauge wire… Without insulation.. AA BATTERIES.. n magnets….but it didn’t work…
I guess the coil windings were quite wide…but I guess the point here is to make a connection between the the battery n the wire…so if I use a large magnet for larger windings ..will it work.??

I followed the instructions carefully but the is not showing any response . I took a new AAA battery , a bare copper wire and 6 neodymium magnet slightly smaller than the battery so can you tell me the problem and the solution too.

I followed the instructions carefully but the train is not showing any response . I took a new AAA battery , a bare copper wire and 6 neodymium magnet slightly smaller than the battery so can you tell me the problem and the solution too. Reply fast as I have to submit my project tomorrow ??

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